The 7th Street Bridge

This is the view of the bridge when it is down. A photo of the plaque is also shown. Note the superstructure of the bridge. Although the bridge is a single leaf, the bridge is still arched in the same way that a double-lead bascule often is. On a side note, the bridge superstructure is riveted together. This bridge was built before bolts took over as the standard.

Bridge In Raised Position

This is what you get to see if you are a car stuck waiting for the bridge to go down.

Bridge In Raised Position

This is the bridge when in the raised position, viewed from beside the bridge. There is only one part, or leaf, to this bridge. Most bascule bridges have two parts, or are double-leafed.

Bridge Going Down

This is the bridge about 75% down. This bridge can be raised and lowered quickly since it is a single leaf bridge. Double-leafed bridges take longer to close since the leafs have to line up just right to close correctly.

On the Bridge

Notice the wooden sidewalk. In the early 1990s, all three of the Port Huron bascule bridges had wooden sidewalks. The 7th Street Bridge was the last bridge with the classic boardwalk, and now it has been removed. The other two bridges now have concrete sidewalks.

The Control Room

This is the main control panel for the bridge. The meter on the far right shows how high the bridge is, in degrees. The wooden-handled crank near the meter is the speed control for the lifting of the bridge. It is what the bridge operator turns to raise the bridge. Two of the three switches in the front of the top of the control panel lower the gates for the northern end of the bridge, and the remaining switch unlocks the bridge so it can be raised. The little silver button on the top of the side of the panel sounds the buzzer to let cars, boats, and people know the bridge is going up or down. The other meters and switches deal with motor speed, and the status of different things. A microphone for the megaphone can be seen on the wall.

The Control Room

This is another view of the main control panel.

The Control Room

This small control panel, at the opposite end of the control room, is for raising and lowering the gates at the south end of the bridge.

Raising The Bridge.

The is a picture of the control panel as the bridge goes up. Notice how the bridge operator is using the lever to control the speed of the bridge as it goes up. Also note the degrees on the meter.

Raising The Bridge.

View out the window as the bridge is going up. Also note the cars being held up at the bridge: perhaps they were wondering why the bridge was going up when there were no boats!

Under/Inside The Bridge

These are the motors that do the work of lifting the bridge.

Under/Inside The Bridge

This is the view above the motors, with various electrical/related things visible.

Under/Inside The Bridge

Another overhead view, showing the various mechanical parts that lead from the motors.

Under/Inside The Bridge

This is the big electrical panel under the bridge. As the bridge goes through the different stages of raising and lowering, these electrical/mechanical switches noisily clack on and off. Since the electrical equipment for this bridge is quite old, there is no real electronics to it.

The Center of Rotation

The 7th Street bridge is a trunnion bascule bridge, which means that the whole leaf of the bridge rotates upon a massive axis, or trunnion, which stays in the same place the whole time. This picture shows the trunnion of the 7th street bridge.

The Counterweight

The massive cement wall to the right is the counterweight for the bridge. The counterweight makes the job of lifting the bridge much easier for the motors.